Where manual paralleling of two AC systems is desired, the frequency of both
systems can be monitored by an LED synchroscope. The systems are synchronised
when the green LED is lit in the 12 o’clock position. The instrument is rated for
continuous operation and connection. For the semi-automatic paralleling of two
AC systems, the voltage, phase displacement and the frequency of both systems
can be monitored by this LED synchroscope and synchro check relay. Controls for
voltage, phase angle, and time delay are provided. The systems are synchronised
when the green triangular LEDs are lit together with the GEN/BUS green LEDs.
A dead bus option is also available.